Australia's vaping laws really do take some understanding. Basically, as explained in this post on Ozvapour.com:
"The baseline is that because nicotine is classed as a Schedule 7 poison in Australia, it’s illegal to sell it except as a licensed medication.
"That means disposable e-cigarettes or cartridges that contain nicotine are not for sale right across the country, but nicotine free ones and refillable devices can be sold unless state law bans them."Read more